Right and left ventricular performance during endotoxin-induced pulmonary hypertension in sheep

We investigated right and left ventricular performance by radionuclide angiocardiography in anaesthetized and instrumented sheep following a (1.5 micrograms/kg) sublethal Escherichia coli endotoxin infusion. Six animals served as controls and five were pre-treated with intravenous Ibuprofen (12 mg/kg). In control sheep an acute five-fold increase of pulmonary vascular resistance (PVR) resulted in a significant decrease of right ventricular ejection fraction (RVEF) and stroke volume. Left ventricular ejection fraction (LVEF) was unchanged as was pulmonary capillary wedge pressure (PCWP). The calculated right and left ventricular end-diastolic volumes (RVEDV; LVEDV) changed significantly in opposite directions during the acute increase of PVR. Right ventricular end-diastolic pressure increased significantly paralleled by an increase of RVEDV. The decrease of LVEDV with an unchanged PCWP suggested a decrease of left ventricular compliance. Pre-treatment with Ibuprofen resulted in complete cardiovascular stability after endotoxin.